Trail jack



Patented Dec. 24, 1946 TRAIL JACK Trevor 0. Davidson, Milwaukee, Wis., assignor to Bucyrus-Erie Company, South Milwaukee, Wis., a corporation of Delaware Application December 9, 1943, Serial No. 513,564

14 Claims. 1

' ing unhitching from and hitching to the hauling device.

Accordingly it is the principal object of my invention to devise a hitch which can be operated with such speed and precision as to reduce this period to the barest minimum.

In addition to my principal objects, above stated, I have worked out a number of novel and useful details, which will be readily evident as the description progresses.

My invention consists in the novel parts and in the combination and arrangement thereof, which are defined in the appended claims, and of which one embodiment is exemplified in the accompanying drawing, which are hereinafter particularly described and explained.

Throughout the description the same reference number is applied to the same member or to similar members.

Figure 1 is a side elevation of my invention, with the trail of the gun on the ground.

Figure 2 is a side elevation of my invention, with the trail in position for traveling.

Figure 3 is a plan view of my invention, in the same position as Figure 2.

Figure 4 is a. side elevation of my limber in traveling position without the cannon.

Referring to the first three figures, We see that It is a conventionalized representation of the mount of a field gun (not shown). It is shown as supported on four rubber-tired wheels l2.

To this mount lltheie is attached a trail l3, in any conventional manner so that the rearend thereof can be raised from and lowered to the ground. This trail serves to brace the gun during firing, and to serve as a means for dragging the gun backwards during moving.

I4 is the axle of a limber, shown as having two rubber-tired wheels l5, and a drawbar I6, which is attached to a wheeled tractor (not shown) or other highly mobile tractive instrumentality. Of course, it could equally well form a part of such instrumentality.

The wheels [5 .are journaled on the ends of the axle M, which axle is in turn journaled' (as at l1, H) to the drawhar l5. An offset curved cable-way l8 is built rigid with the axle id, but might equally well be free to rotate thereon. in

Sill

which event the axle could be rigid with the drawbar it, if desired. All that is important in this connection is that the cable-way be capable of rotating with respect to the drawbar I 6. Other ground support could be substituted for wheels l5.

Pivoted on a substantially vertical pivot integral with cable-way i8 is a lever-arm l9. Other numbered parts of my invention will be mentioned as the description of its operation progresses.

My invention is operated as follows:

The rail l3 terminates in two brackets 20. When the trail is in the position shown in Figure 1, and it is desired to move the gun, the limber is backed over the trail into the position shown in Figure 1. secured to lever-arm l9, by means of a pin or bolt 2|, passed through holes in the lever-arm and the bracket.

A rope 22, pivotally attached (preferably permanently) to lever-arm I9 at 23, passes around cable-way l8, and thence to the usual winch (not shown) possessed by the tractor (not shown).

As soon as the pin or bolt 2! has been set, the winch is actuated to draw-in rope 22, which rotates lever-arm I9 and cable-way it about axle i l as an axis, thus raising the trail to the position shown in Figure 2. It is to be noted that, when the parts are in this position, the connection it between lever-arm i9 and brackets 20 is practically in toggle above axle it. This not only causes axle it to support the weight of the trail by direct compression through lever-arm ill with,- out strain, but also enables the accomplishing of the snug-take-up function (about to be described) by hand, inasmuch as there is practically no weight to be lifted in the course thereof.

Screw 24, which depends from trail l3 has at its lower end an eye, through which it is now secured to lever-arm l9 by pin or bolt 25. Leverarm I9 is then taken up snug against trail l3 by means of screwing hand-nut 26 down against sliding washer 28. Nut 26 is then locked by hand-nut 27.

The cannon can then be towed away.

Lowering the trail into place is accomplished in inverse order.

When the cannon has been towed to its firing position and detached from the limber, screw 25 and. associated parts, which loose from the trail, except when screwed up tight as already described, are lifted up out of place. Then, for the dual purpose of keeping this screw and associated parts from getting lost, and of firmly anchoring the parts or the limber together for The brackets 20 are then pivotally gral with cross-beam 3| the limber, and the screw is clamped to this yoke by screwing handnuts 26 and 21 toward each other, one on each side of the yoke.

Having now described and illustrated one form of my invention, I wish it to be understood that my invention is not to be limited to the specific form orarrangement of parts herein described and shown.

Iclaim:

1. A trail jack, comprising an element adapted to be pivotally supported on a ground-engaging towing vehicle on a horizontal transverse pivot, a, portion of said element in lowered position being adapted to register with a portion of the trail, when the latter is on the ground; means for pivotally securing these two portions together; an offset curved cable-way constrained to rotate with the element; and means for then rotating "the element, to raise the trail off the ground, said means including a rope attached to the element, and passing over the cable-way, and thence to an actuating means; and characterized by the fact that the element has means for securing it to the trail when in raised position; said securing means comprising the following two parts, namely an attaching means supported by the trail, and means [or thereby rotating the element into firm relation to the trail.

2. A trail jack, comprising an element adapted to be pivotally supported on a ground-engaging towing vehicle on a horizontal transverse pivot, a portion of said element in lowered position being adapted to register with a portion of the trail, when the latter is on the ground; means for pivotally securing these two portions together; an offset curved cable-way constrained to rotate with the element; and means for then rotating the element, to raise the trail off the ground, said means including a rope attached to the element, and passing over the cable-way, and thence to an actuating means; and characterized by the fact that the element has means for securing it to the trail when in raised position; said securing means comprising an attaching means depending from the trail, and means for raising the attaching means; said attaching means being a readily removable screw, having at its lower end an eye for attachment to the element, whereby when the towing vehicle is disengaged from the-trail, the eye may be attached to a portion of the element and the screw clamped to a rigid portion of the towing vehicle.

3. A trail jack, comprising an element adapted to be pivotally supported on a ground-engaging towing vehicle on a horizontal transverse pivot,

a portion of said element in lowered position being adapted to register with a portion of the trail, when the latter is on the ground; means for pivotally securing these two portions together; an offset curved cable-way constrained to rotate with the element; and means for then rotating the element, to raise the trail off the ground, said means including a rope attached to the element, and passing over the cable-way, and thence to an actuating means; and characterized by including a screw eye and two nuts, the eye being capable of attachment to the element and one of the nuts being capable of bearing against the trail and being locked by the other nut, and being further characterized by the fact that the towing vehicle has a rigid yoke whereby, when the eye of the screw is attached to the element in raised position, the screw may be secured to the yoke by the two nuts.

4. A trail jack, comprising an element adapted to be pivotally supported on a ground-engaging towing vehicle-on a horizontal transverse pivot, a portion of said element in lowered position being adapted to register with a portion of the trail, when the latter is on the ground; means for pivotally securing these two portions together; an offset curved cable-way constrained to rotate with the element; and means for then rotating the element, to raise the trail off the ground, said means including a rope attached to the element, and passing over the cable-way, and

thence to an actuating means; and characterized by the fact that the cable-way is notched, and by the fact that the element has means for securing it to the trail when in raised position, said securing means comprising a readily removable screw-eye depending from the trail and havcan then be locked to the yoke thereby securing the element against rotation, while the towing vehicle travels without the trail.

5. A trail jack, comprising an element adapted to be pivotally supported on a ground-engaging towing vehicle on a horizontal transverse pivot, a portion of said element in lowered position being adapted to register with a portion of the trail, when the latter is on the ground; means for pivotally securing these two portions together; an offset curved cable-way constrained to rotate with the element; and means for then rotating the element, to raise the trail off the ground, said means including a rope attached .to the element, and passing over the cable-way, and thence to an actuating means; and characterized by the fact that the element has means for securing it to the trail when in raised position, said securing means comprising a screw-eye depending from the trail, and means for raising and locking the screweye.

6. In a trail jack, the combination of: an element adapted to be pivotally supported by a ground-engaging towing vehicle on a horizontal transverse pivot, a portion of said element in lowered position being adapted to register with a portion of the trail when the latter is on the ground; means for pivotally securing these two portions together; and means for then rotating the element, to raise the trail off the groundinto carrying position; further characterized by the fact that in lowered position the means for pivotally securing the element to the trail is substantially below the pivotal axis of the element, and that in carrying position this means is substantially in toggle above said pivotal axis.

7. A trail jack, according to claim 6, further characterized by the fact that the element includes an off-set curved cable-way, and that the means for rotating the element includes a rope pivoted thereto, and passing over the cable-way, and thence to an actuating means.

8. A trail jack, according to'claim 6, further characterized by the fact that the element has m nosi lo is disengaged from the treil, the eye may be etinched to e. portion of the element and the screw clned to e mgid portion of the towing vehicle.

10. A tneii jack, coco: to claim 6, funther characterized by including it screw eye and two mate, the eye being capable of ottechment to the element and one of the nuts being cnnebie oi be against the ti'eil end; being locked by the other nut, and being further charecterized by the fact that the towing vehicle has a. rigid yokewhei'eby, when the eye of the screw is attached to the element in raised position, the screw may be secured to the yoke by the two nuts.

.11. A treil jack, according to claim 6, further characterized by the fact that the element includes an ofi'set curved cable-way, and thntthe means for rotating the element includes a. rope pivoted thereto, and m over the cable-way, and thence to en actuating e and by the feet that the element has means for securing it to the trail when in raised position, (1

1.: corn z-i an 1.;

b th treiLend rted 1.1; mils 35 the trail, end means for n:

tion, acid securing m removable screw-eye depending from the trail 'and. having e washer thereon, and two nuts to ecco to claimG, iurthei i d by the fact that the element'inudes n notched 08sec curved cable-way, end

t the means for rotating the element includes a rope pivoted thereto, and w over the cable-way, and thence to an actuating means: m; by the feet that the element has means for sec n it to the trail when in raised nosicomprising a, readily raise and lock the screw; said element also hav- 7 ins means for attachment to the eye when said element is in raised position, and the towing vehicle having a. rigid yoke, whereby the washer can be inserted in the notch in the cable-Way, and the screw can then be locked .to the yoke, thereby securing the element can rotation while the towing vehicle travels Without the trail.

'13. A trail jack, to claim 8, further characterized by the fact that the element has meens-ior seeming it to the trail when in raised position, esid securing means comprising a, screweye depending from the tmil, and means for raising ioc w the screw-eye.

is. n treii jack, according to claim 6,- further characterized by the fact that the element includfi on ofiset cu cable-way and that the means for rotating the element includes a, rope.

pivoted reto, and and thence to en actun over the cable-way, means; and by the fact that the element has cans for securing it.

to the trail when in raised m 3,1 3.

position, said securing comps a, screw-eye depending from and locking the 

